While the mammalian Y chromosome (males only) may be much smaller than the X chromosome that predominates in females (males have one X, females two), this males only chromosome is evolving much faster. As a result male primates were found to be evolving faster than females. (Source: Nature.com)

The Y chromosome is evolving fast to deal with genetic pressures of varying mating habits, such as chimp group mating

Modern biochemistry and genetics is just beginning to unlock the complex secrets of evolution, the process in which organisms change over long periods of time through random genetic variation and selective pressures. With a handful of genomes sequenced, scientists can now start mining this data to find interesting trends and evidence of the course evolution is taking, particularly in humans.

A provocative and intriguing new study reveals that past thought on the Y chromosome, the chromosome that instructs mammals to develop into males, may be entirely flawed and that the chromosome, previously thought to evolving at a crawl, may in fact be evolving far faster than other chromosomes. Human females typically have two X chromosomes, while males have an X and a Y chromosome.

It was previously thought that autosomes (non-sex chromosomes) and the X sex chromosome featured greater diversity (faster evolution) than the Y sex chromosome, a smaller chromosome. According to the new study, led by Jennifer Hughes, a postdoctoral researcher in Whitehead Institute Director David Page’s lab. The research indicates that primate males may be evolving significantly faster than females.

To determine how fast the Y chromosome was changing, the scientists needed a point to compare our Y chromosomes against. The human Y chromosome had been comprehensively sequenced by the Page lab and the Genome Center at Washington University in 2003. A promising target was DNA from chimpanzees -- a close relative of humans on the evolutionary tree. However, the 2005 sequencing of the chimpanzee genome excluded the Y chromosome, mostly, due to its hundreds of repeating sequences that threw off sequencing techniques at the time.

Undeterred, researchers at the Page lab and Genome Center at Washington University completed sequencing the chimpanzee Y chromosome, using newer techniques. What was discovered was amazing. The Y chromosome, thought to be a musty unchanging stretch of genes had changed significantly between humans and apes in terms of structure and content. Approximately one third to a half of genes found in the human version of the chromosome were lost in the chimp chromosome, since chimps diverged from humans in the evolutionary tree.

Professor David Page compares these changes to a constantly renovated home, stating, "People are living in the house, but there’s always some room that’s being demolished and reconstructed. And this is not the norm for the genome as a whole."

Wes Warren, Assistant Director of the Washington University Genome Center, another top genetics expert, agrees that the findings are extraordinary, "This work clearly shows that the Y is pretty ingenious at using different tools than the rest of the genome to maintain diversity of genes. These findings demonstrate that our knowledge of the Y chromosome is still advancing."

One thing that may be driving faster evolution of the male sex chromosome is differing mating habits between species. Where as humans typically take a single partner during sexual intercourse, numerous chimpanzees often mate with a single female in a short time period. Males who produce more sperm, or whose sperm is better at impregnating females will have a better chance at beating the other males' sperm and passing on his genes.

To give an idea of just how profound this effect is, the difference between the rest of the human and chimp chromosomes is only 2 percent. That means that the male sex chromosome is evolving nearly 15 times faster, or more, on average than the female genome.

The Page lab and the Washington University Genome Center are now looking at the Y chromosomes of several other mammals to further determine if this faster rate of male evolution is a characteristic of primates only, or other mammal lines as well.

The study on the work was published in the prestigious journal Nature, and can be found here.

The research was funded by National Institutes of Health (NIH) and the Howard Hughes Medical Institute (HHMI).

Where as chimps have evolved to cope with the genetic pressures of group sex, human males and females have evolved on a different course. Recent research indicated that human females are slowly evolving to be shorter and to carry more weight.

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You shouldn't pin a god as the creator of things that humans cannot currently explain. My bio professor mentioned that when humans do things like this, as time goes on and things are discovered that leaves less and less for the god to do.

Also, if you ever took a genetics class(I'm in one currently), or higher level Biology classes(In these too) you'd know that Humans and Chimps are closely related(think Step bro and sis, sort of). Humans did NOT evolve from chimps, they both evolved from a common ancestor.

There are multiple markers that makes it impossible for Chimps/humans/Orangs/etc. not to be related by some unidentified common ancestor.

It's been about a year since I went over evolutionary biology, but these are the things I can remember:- Humans and Chimps share a high 90's percent of genetic homology. (98.5% sticks out though, not just from the article)- Thousands of ancient pseudogenes(fossil genes) that are identical in both chimps and humans, in the same exact location.- A chimp has two more autosomes than humans do, but, if you merge the 12th and 13th(I believe) autosomes of chimps, you have a nearly identical chromosome to a human's number 2 chromosome.- Ancient Viral DNA is in the exact same places in both humans and chimpanzees(even with the 12/13 chimp chromosome and #2 human chromosome).-Transposons/retrotransposons, but I wont go into those. :]

There are many other indicators, I just can't think of them off the top of my head for some reason.

Just because Chimps and humans share common DNA does not mean they evolved from each other or even a common ancestor, that is just another evolutionary assumption, that if you share common DNA than you must have a common ancestor, but actually humans share a high % of common DNA with a lot of species such as chickens and weirdly earthworms.

As well that 1-2% difference in DNA between chimps and humans is an enormous genetic difference. Comparing chimps and humans is like comparing the first computer to my modern i7 gaming rig, similar components, huge difference and mine can play Crysis :).

As this is a tech site I like to use tech analogies, think of God using DNA/RNA as the programming language like a programmer use’s C++, since a common language is used all species or programs will share DNA and may share more or less depending on biological features.

quote: Think of God using DNA/RNA as the programming language like a programmer use’s C++, since a common language is used all species or programs will share DNA and may share more or less depending on biological features.

This doesn't do anything to explain a multitude of things that are present in the genetic record, things that evolution does a good job of explaining.

Why do all marsupials (for example) share variations of genes that are more similar than than same gene in other mammals? More generally, why can a scientist predict with good accuracy which animals will have the most similar coding for a protein? Why is it that if I map species by similarity of a protein, that same map is held to if I do the analysis on a different protein?

Being a programmer, I also like to use tech analogies, and the only analogy that I can think of that fits what we see in genetics is a Genetic algorithm (i.e. one that simulate evolution to solve an engineering problem).

A genetic algorithm looks at the fitness level of offspring of existing populations. So an existing population with genetic material must already exist for this algorithm to work. This algorithm does not exist in nature, as the body does not run an algorithm before it reproduces, so it is very unnatural, aka not a driving force of evolution. It can predict genetic diversity and fitness within a population, but it does not create it. Also a programmer has to create the genetic algorithm, just like a programmer had to create C++. What you are saying is this very complex programming language we call DNA created itself?

What I want to know is?

1. How did the DNA code come into existence?2. How does it evolve? From one cell to a human…and don’t say by a build up of mutations.. as that argument is old, tired and shot full of holes.

The 'Algorithm' in nature that selects who gets to reproduce is called natural selection. In a genetic algorithm, a fitness algorithm is run to determing which parts of the population 'survive' and get to reproduce and which parts don't. The same way that unfit animals (or plants, or bacteria, or any living thing) never get the chance to reproduce, whereas fit animals do.

Honestly, once you admit A) DNA is the instructions for life and B) DNA copying is imprefect, everything else follows from there. Imperfections in the copy will manifest themselves in the child organism. Most imprefections will cause problems, but some small number of them will improve survival chances. The child organism that recieves mutations that improve survival chances are more likely to reproduce.

That's all that evolution is saying, if you can find a flaw in that argument, have at it. But 150 years of research, catologing, and critical thinking haven't been able to.

Haha, no Dailytech article would be complete without a reference to Crysis. :P

Firstly, if there were a few common links like I mentioned in between the organisms then I would agree with you that it could be a coincidence that everything could fall into the same categories. But, seeing as how there are thousands upon thousands of coincidences between the two different organisms, it shows that *beyond a reasonable doubt* shows that the two share a common ancestor [Science doesn't prove, heh, almost made that mistake].

Of course that 1-2% difference is enormous; if it wasn't, chimps would either be much more intelligent than they are(some species of chimps have a very crude language) or humans would be much more stupider. :P haha

You can also add the fact that there are thousands of point mutations in the exact same spot on both chimps/humans genomes [and to a lesser degree other animals].

I don't think creationists are saying man is not smart enough to figure out how all things work...they are saying that the scientific evident shows that our universe and life had to be spontaneously created by God, not through mysterious “natural forces” as evidence and logic point away from these natural forces being able to create our world, cells, life, etc.

Think about it, creation is actually quite logical as humans have created and continue to create millions of items, computers, cars, etc., out of the building blocks of the universe. Creation is something that we see and do on a daily basis, just like the program I used to write this post which was created by a human, not through “natural forces” why couldn’t God with his superior intelligence create biological life, like we create say an artificial intelligence.

1) Creation is too complex to have come about without assistance. (In the building block model the blocks were created)

2) The Creator who is able to design and build a Universe is too complex to have come about without assistance.

3) The Creator who is able to design and build a Creator who is able to design and build a Universe, is too complex to have come about without assistance

4) The Creator who is able to design and build... (insert 3) This is a recursive statement that follows the pattern of 1, 2 & 3

Since there is an infinity of Creators needed to create our Universe and a Creator is required who is capable of initiating that infinity, we now have an Aleph 1 infinity of Creators capable of creating Creators capable of creating the infinity in the above recursion. Since this higher order infinity requires a Creator we now have an Aleph 2 infinity. By the time this argument is taken to it's logical extreme we then have an Aleph infinity infinity. Of course this infinite infinity requires a Creator...

The usual response of Believers is that God does exist, therefore it follows that God could spring into existence spontaneously & having done so, God then created the Universe so that there would be someone to know that God exists. It follows from this belief that failure to properly believe in God results in Bad Things.

God springing into existence spontaneously and then creating the Universe is of course much more likely than a sequence of chemical reactions driven by energy in the surrounding environment giving rise to sequences that tend to create a favorable envoronment for those sequences.

That the evidence indicates that either God designed those initial sequences and sat back to watch or that they arose by chance is disregarded. Also disregarded is that the Genesis story is not the only creation myth. Once you postulate that a Creator did it, you then have to decide which of the multiple religions (if any) tells the story correctly.

If you would like to think of why we exist, do research into the atoms and how these function. To put it in a short sentence : Life exists because it can exist. There is a driving force but not an intelligent designer. The universe was once to energetic to support life. Now the universe is in a phase where life can flourish. At a certain time there will not be enough energy to support anything and thus no life. What will happen then ? Who knows. The universe may cease to exist and a new one will appear or the universe will be replenished again. Or it will just simply stop. Time is a part of us. Whatever it may be that was the start of our universe. Perhaps it was time it self...

It is difficult to accept for most people that chaos leads to new chances, opportunities. When there is no chaos, there is nothing. The only issue is, chaos exist only in the minds of those who refuse to accept that chaos is build up of more complex patterns then the human mind can grasp. Therefore, a god is born in the mind of humans...

quote: Think about it, creation is actually quite logical as humans have created and continue to create millions of items, computers, cars, etc.

Yeah, *think* about it. Some guys from 1500~2500 years ago didn't know much about technology and such because they didn't have computers, high powered telescope or lasers so when their 8year old kid asks "why is the sky blue", they can say "God made it", because MAN didn't understand how the sun light was effecting the molecules in our atmosphere.

Um, we know why the sky exists. Gravity holds a gaseous atmosphere close to the surface of the earth.

So let me get this straight. You want to take the theory of evolution, which has a substantial amount of evidence supporting it with only a few things yet to be explained, and completely throw it out for a theory about a magical man in the sky that instantly created everything that has absolutely no evidence to support it in any possible way?

Well, you got 1 out of 2... The point was that early MAN, who did not understand HOW things work (gravity, energy, etc) - after-all, up through the 1800s, men thought that heat worked like a liquid. They also didn't know about blood types at first - they were puzzled when some of the first blood transfusions worked and some didn't.

quote: Question 2. why does the sky exsist? God created it

PROVE IT

We have theories based off of viable science. Your Q#2 is based off stupidy / naiveness of men thousands of years ago.

This is why WE go to school, to learn. Otherwise, we're stupid monkeys with guns.

Er, we (intelligent men) developed computers, lasers, scopes that can allow us to see the BILLIONS (not hundreds or thousands) of Galaxies in the universe.

quote: God is a he because Jesus is God

What are you? Seriously?

Its pretty bad when you guys don't even understand your own religion, its funny as hell. Lets do a little lesson plan, lets see if you can follow it. I won't hold your hand on this because your flaws are scary typical.

A: Question: how many Gods in your religion?

B: If Jesus is the Son of God, then Jesus CANNOT be God!

C: If Jesus is God (as you just stated), then he created himself... but that goes against the bible (of how many interpretations?).

D: "I am Second" campaign is flawed. Its a religious group in which Jesus is 1st and YOU are 2nd behind Jesus. er... okay, then God (creator of Earth & heavens) is 3rd? LOL thats some funny stupidity.

E: To be closer to Jesus, convert to Judaism.

F: If God is perfect and Man is created in his image, therefore God is... "A man", then (A) God is not a super-being or (B) if God was, as shown by mankind's stupidity, defects, health, war, murder, rape, etc then prove that God is imperfect and a rather sick individual with childish ego problems. As shown by your own faith: Worship me or *I* will send your to hell, EVEN thou I gave you free will because *I* Looooove you.

I beleive you are grossly ignorant of religions. To claim that he doesn't even understand his own religion when you do not know of which religion the person is, is quite frankly stupid.All assumptions of whether any of this is true or not here are some answers to your crappy attack of christianity.A:3, ever hear of the trinity, God the father, God the son, and God the holy ghost?B: Jesus can be God, as all 3 are God.C: Nope, God the Father and God the son explain that part.D: You're point? Some peoples views do not reflect all others and may not even be this person's religious belief systemE: Do you screw your dad to be closer to your mother? No, you get to know the person, not do the things they do.F: or C God created man in his own image, and not an exact 1:1 copy of himself and allowed them to develope their own brain and choices over time.You're concept of hell also does not match everyones either.It's either accept this God's payment for your sins or be full of sin in the presense of god when he returns, whereby sin is ungodliness and in the presence of god in is blazing glory one is destroyed forever...

quote: when you do not know of which religion the person is, is quite frankly stupid.

Its easy to figure out from his "Jesus" thingy that he's not: Islamic, Jewish, Buddhist, Shinto or Catholic. So no, it would be stupid to not be able to figure that out.

quote: answers to your crappy attack of christianity.

I'm not attacking Christianity. Just stupidity and organized religion.

A: Ever hear "There is no God but God?" Just as meaningful, eh?

B: So, Gos has split personality disorder? My Son is not me, I am not my son. Jesus was not God, for God is only God. Filling two entities into the same title is stupid, er never mind, (bush & cheney were both president - duh)

C: So? It goes back to the stupidity of combining two people into one.

D: I wasn't being specific to the poster. I was explaining the stupidity of a religious marketing campaign that effectively puts their God below man. And BEFORE you go back to the God is he/Jesus blah, that campaign is supposed to be aimed at people who don't know/think they know the Bible.

E: But many Christians hate Jews. Thing is, the Christian Bible has been re-written over and over again (the new 2010 version!), while Judaism is still the same.

F: Or if God created everything; he created homosexuals, blacks, Islam, the air, malaria, fleas (explain why Noah saved the 2 Fleas), cancer, baldness, incest and more. If Adam & Eve were the first two humans, who did their children have sex with to reproduce? ewwwwwwwwwwww!But in the end, your God has an ego problem in that if YOU choose to not follow the bible to the letter (you can't, due to interpretations and contradictory rules, ideas and stories) - you're damned. So wheres the love?

quote: You're concept of hell also does not match everyones either.

Huh? Did I describe hell? I was going by the interpretations of the religions.

quote: t's either accept this God's payment for your sins or be full of sin in the presense of god when he returns

So a child molester who rapes his own children and goes to Church twice a week is forgiven by God, but an Indian in South America whose never meet a white man goes to Hell? Sounds perverted to me.

Remember, white men from Europe thought the Earth was flat and that their ships would fall of the Edge of the world. Too stupid to understand the stars and the moon. Yet men from thousands to years before understood a lot more, even calculated the size of the Earth roughly. It was religion that taught those men that the Earth why flat. hmmmmmm.

quote: Stick to science when you argue against religion.

Stick to Religion as it doesn't belong in Science, the Government or our schools.

The universe is full of more galaxies than there are humans. Never mind the 100~200 billion stars in our galaxy alone.

Thinking about it, now I think that is the reason why religious people don't believe in pollution or global warming issues. Expecting the big guy above to magically fix the AIR and maybe create another planet or whatever to feed the people.

"So, I think the same thing of the music industry. They can't say that they're losing money, you know what I'm saying. They just probably don't have the same surplus that they had." -- Wu-Tang Clan founder RZA